lilinjun is right on the leaving aspect. Naan - leavened with yeast/baking powder/yogurt or a combination. Roti - unleavened. And yes, roti is usually made with whole wheat flour and naan from all purpose flour. Generally naan is not made in homes in India - either made in communal clay ovens in the villages or clay ovens at restaurants or truck stop eateries. Roti, is the staple make-at-home-everyday bread. Cooked on a griddle and often, at the end directly on the flame where it puffs up.I'll see if I can find a recipe online that I like for roti and post a link here. As for naan, if something works for you, let me know. :)

Naan is dough stretched out and slapped on the inside wall of a ceramic jar oven.

Roti is rolled into a huge circle, well greased, I mean, absolutely slathered, then you pick it in the center and it will form sort of a sloppy rope hanging down that you drape into a flat coil which you pat together a little and cook on a griddle. When it's done on both sides, you slap the top a couple of times and the rolling/twisting plus grease has made layers that flake apart. Yummy, but filling, and you can make them sweet or savory.

And yes, I have made both. Roti take some time to get the hang of, but even the imperfect ones are yummy.

The above roti description is as learned in a Thai cooking class. I assume that there are regional variations across south & southeast Asia. For example, we did not use ghee, but coconut grease, and quite a bit at that!

We made them sweet-with condensed milk, and savory-with a very saucy red curry of beef. Both were absolutely delicious and, bonus, the roti was fun to make, but so heavy and filling that afterward it was about all any of us could do to stagger out to our cars.

Yes, I know what Louise is describing as paratha, and there are different ways to shape after the ghee is brushed on--some roll and then coil it, some fold it in quarters before rolling, others do a sort of croissant like envelope shape. I like the coil, as it yields pretty consistent results.